How do you test a slewing bearing?
One of the most basic indicators of slewing ring bearing problems is the condition of the lubricant. If metal particles or flakes are apparent, some form of wear is taking place. Grinding, popping, or clicking noises from the bearing typically mean there is inadequate lubrication and/or excessive wear in the raceway.
What is a slewing bearing used for?
A slewing bearing or slew[ing] ring (also called a turntable bearing) is a rotational rolling-element bearing that typically supports a heavy but slow-turning or slowly-oscillating loads in combination (axial, radial and moment loads), often a horizontal platform such as a conventional crane, a swing yarder, or the …
What is crane rocking test?
The rocking test comprises the measurement of the deflection between the crane pedestal and the rotating crane housing in the way of the slewing ring using a dial test indicator to determine the bearing clearances.
What is a slew ring on an excavator?
Kaydon slewing ring bearings. In big rotating equipment, such as cranes, excavators and tunnel boring machines, a slewing ring bearing must simultaneously handle a complex load spectrum that covers diverse combinations of thrust, radial and tilting moment loading.
What is slewing in crane?
Slewing is the rotation of an object around an axis, usually the z axis. An example is a radar scanning 360 degrees by slewing around the z axis. In crane terminology, slewing is the angular movement of a crane boom or crane jib in a horizontal plane.
How do you measure a crane rocking test?
The measurement should be done as follows: Measurement points normally marked at the pedestal. Measurement should be done by depth meter at four directions of boom: FWD, AFT, PORT and STBD. At each boom direction two or four readings must be taken (see item 1 above), check maker’s recommendations for details.
What is rocking test of crane & how frequently you should perform it?
every six months
-‘Rocking tests’ are carried out every six months and that the results are recorded and monitored in order to ensure the wear tolerances remain within the limits. – The ship is adjusted to have least possible trim, preferably on even keel. – Bad weather / Windy situations are avoided.
How does an excavator slew work?
In operation, the slew drive’s axial movement, or motion around its axis, interacts to create radial torque. The action occurs by meshing the grooves of the horizontal screw with the teeth of a perpendicular gear. While turning, the worm gear’s axial movement transfers magnified torque force to the radial gear.
How does a slewing ring work?
Slewing bearings comprise an inner ring and an outer ring, one of which usually incorporates a gear. Together with attachment holes in both rings, they enable an optimized power transmission with a simple and quick connection between adjacent machine components.
What is slew on excavator?
Slewing refers to rotating the excavator’s house assembly. Unlike a conventional backhoe, the operator can slew the entire house and workgroup upon the undercarriage for spoil placement.